Solar energy aims for the 'impossible'

If you think about it, it’s crazy for us not to try and find every way possible of harnessing energy from the sun. After all, the sun is pretty much the source of every other power source we’ve tapped: wood (try growing a tree without sunlight), oil (brewed from photosynthesizing microorganisms that lived millions of years ago), wind (caused by uneven thermal heating of the atmosphere). Even nuclear energy wouldn’t be possible if it weren’t for heavy elements like uranium that are the by-products of fusion from stars far older than ours.

Solar photovoltaics have already dropped dramatically in price, and have been widely deployed in Germany, Spain and the US, among others. Meanwhile, concentrating solar power coupled with molten salt technology makes it possible to store the sun’s energy for use at night and during inclement weather. Could sun power one day replace every other source of energy we now depend on? While it sounds impossible, there are quite a few projects aimed at making such a goal possible:

• Sun Catalytix, founded by leading energy researcher Daniel Nocera of the Massachusetts Institute of Technology, aims to use the sun’s energy to split water into oxygen and hydrogen gas, which can then be stored and used as a fuel whenever needed. According to the company’s website, “The elemental components of just 3 gallons of water have enough energy, when recombined, to satisfy the daily energy needs of a large American home.”
• Meanwhile, Joule Unlimited (formerly Joule Biotechnologies) continues its quest to develop its trademarked (but not yet commercially available) Liquid Fuel from the Sun. It recently signed a lease for 1,200 acres of land in New Mexico on which it plans to build a demonstration facility to produce renewable diesel and ethanol fuels. How long before we see that happen is anyone’s guess at the moment.
• Another US venture, this one led by the Department of Energy (DOE), has a goal of bringing the total cost of solar photovoltaics down to $1 per watt by 2020, which would make solar panels competitive with other energy sources, no subsidies required. The SunShot Initiative’s name was inspired by President John F. Kennedy’s “moon shot” speech that led to the first human landing on the moon in 1969.
• A Colorado startup, US e-Chromic, hopes to use DOE technology to develop sun-smart windows that can electrochromically change windows from transparent to reflective to reduce cooling needs in buildings on hot, sunny days.
• Could a peaceful, democratic resolution to the Arab Spring plant the seeds of a global clean-energy infrastructure? That’s the mission — more of a dream at this point, actually — of the DESERTEC Foundation, a project being led by companies such as Munich Re, Deutsche Bank, Siemens and ABB. In theory, tapping the solar energy that falls onto just a small portion of the Sahara could meet the planet’s energy needs. If the financing and construction challenges didn’t seem daunting enough, however, the political upheaval taking place in some of the key DESERTEC target countries — Libya, Egypt, Algeria and Yemen, among others — make the project appear all but impossible for now.

Could the impossible one day become possible? More and more, it appears to be not so much a question of technology, but of scalability, affordability, time, policy and sheer determination.